CHICAGO – Two of the largest U.S. mortgage servicers have said they will resume home foreclosures, but a big-city sheriff has news for them: he won’t enforce their foreclosure evictions.

The sheriff for Cook County, Illinois, which includes the city of Chicago, said on Tuesday he will not enforce foreclosure evictions for Bank of America Corp, JPMorgan Chase and Co. and GMAC Mortgage/Ally Financial until they prove those foreclosures were handled “properly and legally.”

Bank of America, the largest U.S. mortgage servicer, and GMAC, on Monday both announced rollbacks from their foreclosure moratoriums.

The announcement by Cook County Sheriff Thomas Dart comes after weeks of damaging accusations of shoddy paperwork that may have caused some people to be illegally evicted from their homes.

“I can’t possibly be expected to evict people from their homes when the banks themselves can’t say for sure everything was done properly,” Dart said in the statement.

“I need some kind of assurance that we aren’t evicting families based on fraudulent behavior by the banks. Until that happens, I can’t in good conscience keep carrying out evictions involving these banks,” he added.

Bank of America, GMAC and JPMorgan Chase along with their subsidiaries, make up around a third of the roughly 3,700 eviction orders filed at the Cook County sheriff’s office, the statement said.

The foreclosure controversy, which has drawn public outrage and sparked government probes, has threatened bank earnings and the health of the fragile housing market.

Two years ago Dart refused to carry out foreclosure evictions in cases where renters apparently had not been informed that they were about to be evicted from buildings in which their landlords had fallen into foreclosure.

Some 20 Cook County sheriff’s deputies execute around 14,000 foreclosure and rental eviction notices every year.